Moisture control method and system for wheel excavators



July 20, 1965 R 3,195,251

MOISTURE CONTROL METHOD AND SYSTEM FOR WHEEL EXCAVATORS Filed March 19, 1963 INVENTOR.

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United States Patent 3,195,251 MOHSTURE CGNTROL METHOD AND SYSTEM FOR WHEEL EXCAVATORS Fonad K. Mittry, Jr., Los Angcles, Calih, assignor to Mechanical Excavators, Inn, Los Angeles, Calif., a

corporation of California Filed Mar. 19, 1963, Ser. No. 266,366 12 Claims. (Cl. 37-490) This invention relates to the handling of agglomerate material, and particularly to a system and method of controlling the moisture content of agglomerate material.

Accordingly, a primary object of the invention is to provide a wheel excavator which continuously discharges a stream of excavated material having a controlled moisture content.

Another object is to provide a moisture control system for a wheel excavator or other agglomerate material handling system which is capable of controlling the moisture content of excavated material discharged from the wheel excavator or system to a very close degree.

Yet a further object is to provide a moisture control system for a wheel excavator which includes water regulating means for controlling the amount of water added to the excavated material in coordination with the flow of excavated material.

Yet a further object is to provide a method of controllably adding moisture to agglomerate material in response to the quantity of agglomerate material passing a material sensor located in the material flow path.

Other objects and advantages of the invention will become apparent from a reading of the following description of the invention.

The invention is illustrated more or less diagrammatically in the accompanying drawing, wherein:

FIGURE 1 is a side elevation of a wheel excavator; and

FIGURE 2 is a detailed view, to a larger scale and partly diagrammatic, of a control system for adding moisture to excavated material passing along the discharge conveyor of the wheel excavator of FIGURE 1.

Like reference numerals will be used to refer to like parts throughout the following description of the drawing.

A wheel excavator is indicated generally at in FIG- URE 1. The excavator includes a base 11 which rotates about a crawler track 12. A power plant 13 located at' the rear of the base supplies power to drive the excavator wheel and the various auxiliary motors.

A six bucket excavator wheel is indicated generally at 14. The wheel is carried at the end of a ladder structure 15 which is connect-ed at its inner end by any suitable means, not shown, to the rotating base 11. The mast 16, gantry frame structure 17, and suitable cables 18, 19, the latter of which may be retractable, support and control movement of the ladder and digging wheel in a generally vertical plane.

The digging wheel continuously discharges onto a ladder conveyor 20. Material is discharged from the ladder conveyor into a swivel spout 21. The swivel spout in turn discharges into a hopper 22 located at the lower end of the discharge conveyor 23. The discharge conveyor is pivotally secured to the rotating base at its lower end and supported by suitable cables 24, 25 or any other suitable means from gantry frame 17. An operators cab is indicated at 26.

The discharge conveyor discharges into a multiple discharge spout indicated generally at 30. In this instance a pair of discharge chutes 31, 32 have been shown, the spouts being arranged in tandem with respect to the longitudinal axis of the discharge conveyor so that trucks or other haulage vehicles or means may be positioned side by side therebeneath to remove the excavated material.

3,1 ,25 1 Patented July 20, 1 965 Referring now to FIGURE 2 the discharge conveyor 23 consists essentially of a pair of end pulleys 34, 35 around which is trained an orbitally movable endless conveyor belt 36. The conveying reach 37 of the belt it supported at substantially regular intervals by a plurality of idler assemblies 38. The return reach 39 is preferably supported at intervals of greater length by return idlers. Any suitable means, such as a conventional electric motor, may be employed to drive the discharge,

conveyor. Excavated material 40 which is deposited at the tail end of the conveyor moves towards the head or discharge end in the direction indicated by the arrow.

The two-way discharge spout 30 consists essentially of a hood section 41 which opens into the twin chutes 31 and 32. A pivoted gate is indicated at 42. The position of the gate, and consequently the chute down which the excavated material flows, is controlled by hydraulic cylinder 43. When piston 44 and piston rod 45, which is connected to the butterfly valve gate 42, is in its retracted position as shown in FIGURE 2, chute 31 is locked and the excavated material flows through chute 32. When piston 44 is extended the gate 42, which is then in the dotted line position, blocks chute 32 and the excavated material is deflected into chute 31. Any suitable piping may be employed to control the operation of cylinder 43, and consequently the gate 42. In this instance an air line is indicated at 46, but it is quite within the scope of the invention, however, to utilize a hydraulic or other fluid type control medium.

A water supply system for adding water to the excavated material is indicated generally at 50. It includes a water supply line 51 which communicates with any suitable water source, such as water wagons. A globe valve is indicated at 52 and an adjustable time delay valve at 53. The water line is connected to the center port 54 of a two-way shuttle valve 55. Branch conduits 56, 57 terminate at spray nozzles 58, 59 respectively. The nozzles are positioned to direct a spray of water against the excavated material as it passes through chutes 31, 32 respectively.

The position of the shuttle valve is controlled by a shuttle valve operating cylinder 60. Piston rod 61 is pivotally connected to arm 62 which in turn controls the position of the valve member within the shuttle valve. The position of piston 63, and consequently the position of the shuttle valve, is controlled by the admission and discharge of fluid from the cylinder through branch conduit 64. in the FIGURE 2 position the shuttle valve has been positioned to connect branch conduit 57 with the water line 51 so as to cause water flow only through nozzle 59.

The volume rate of flow of water through pipe 51 is regulated by the control system indicated generally at 70.

The control system for regulating the spray of water against material in the discharge chutes includes a scale 71 which, in this instance, consists of a platform 72 supported on return springs 73. A stem 74 extends downwardly from the center of the scale platform and is secured at its lower end to a piston 75 which is slidably received in spring loaded actuator cylinder 76. A work ing fluid, in this instance air, is alternately compressed and expanded in chamber 77 by the movement of piston 75. 7

Chamber 77 is connected to pressure chamber 78 in positioner cylinder 79 by line 80. The positioner cylinder includes a spring loaded piston 81 from which piston rod 82 extends. The piston rod carries a valve member 83 at its outer end which controls flow of water through valve 52 as will be apparent from the following description of operation.

Suitable adjusting means, indicated at 84, 85 enable a the length of stem 74 and flow controller 33 to be varied as needed.

The use and operation of my invention is as follows:

Agglomerate material, such as excavated material dug out by the Wheel excavator of FIGURE 1, is frequently too dry for further processing in its as dug condition. My invention enables the moisture content of the excavated material to be very closely controlled so that the material when deposited on the removal means requires little, if any, further moisture.

In the following description of operation it will be assumed that excavated material 44 has not reached scale beam 71.

As the excavated material passes over idlers 38a, 38b, and 380, scale beam platform 72 is depressed, the extent of movement of the beam being proportional to the weight of material thereabove. Downward movement of the scale beam depresses the piston 75 in air operated actuator 76. Downward movement of the piston 75 is translated into outward movement of positioner piston 81. The movement of piston 81 is a direct function of the weight of the material passing over the belt. Movement of piston 81 to the right in turn opens globe valve 52 to permit water to flow through it.

Opening of the globe valve does not immediately result in a spray of water to nozzle 53$ or 59 because time delay valve 53 remains closed. Opening of the time delay valve is remotely controlled, its purpose being to prevent water fiow from starting until excavated material has passed over the scale platform and has reached the chute entrance.

Water flows through either branch conduit 5a or 57 depending on the position of the valve in shuttle valve 55. In this instance the shuttle valve control cylinder 60 has been connected into the line leading to gate control cylinder 43' in such a manner that when the gate is in the FIGURE 2 position water flows through branch conduit 57, Whereas when gate 42 is in the dotted line position water flows through. conduit 56.

Although, a preferred embodiment of my invention has been illustrated and described, it will be at once apparent to those skilled in the art that other modifications may be made without departing from the spirit of the invention, Accordingly it is my intention that the scope of the invention be limited, not by the above exemplary description, but solely by the scope of the claims when interpreted in light of the pertinent prior art.

I claim:

1. In combination in a wheel excavator,

an excavator wheel,

conveying means,

said excavator wheel being constructed and arranged to continuously dump excavated material onto the conveying means, said conveying means being constructed and arranged to continuously convey excavated material along a continuous flow path to a pair of discharge chutes,

structure for supporting the excavator Wheel and conveying means, a deflector located in the continuous flow path upstream from the discharge chutes,

means for moving said deflector from a first position in which excavated material is directed to a first discharge chute to a second position in which excavated material is directed into the other discharge chute,

a water supply line communicable with a source of water,

said water supply line terminating in a plurality of outlets, one outlet opening into each discharge chute, means for directing Water flow into the discharge chute through which excavated material is passing, and means for regulating the quantity of water directed into the active discharge chute in consonance with the quantity of excavated material passing along the continuous flow path.

2. A moisture control system for a wheel excavator or the like having an excavated material flow path which terminates in a plurality'of discharge areas and means for diverting excavated material from one discharge area to another, said system including, in combination,

a Water supply line communicable with a source of water,

said water supply line terminating in a plurality of outlets, one outlet opening into each discharge area,

means for directing water into a moving stream of the excavated material as it passes through a discharge area, and I means for vregulating the quantity of water directed into the discharge area inconsonance with the mov ing stream of excavated material passing through the quantity of excavated material moving along the flow path.

3. The moisture control system of claim 2 further characterized by and, including valve means in the Water supply line,

a signal generator actuable by the presence of lowing material, said signal generator generating a signal the intensity of whichris proportional to the amount of excavated material passing along the fiow path, and

means for transmitting the signal to a regulator the valve means,

said regulator being effective to regulate the flow of Water to the discharge areas.

4. The moisture control system of claim 3 further including means for delaying flow of water to the discharge areas to thereby insure commencement of Water flow in the discharge areas substantially simultaneouslywith the commencement of flow of excavated material therethrough. V

5. A moisture control system for a wheel excavator having a discharge conveyor which terminates at a twoway discharge spout, said spout having'a pair of discharge chutes and gate means for diverting excavated material from one chute to another, said system including, in combination, I

a water supply line communicable with a source of water,

said water supply line terminating in a plurality of water outlets, one outlet opening into each discharge chute,

. value in the water supply line effective to alternately divert water to one outlet or the other depending upon which chute excavated material is passing through, 1

a control cylinder operable in unison with the gate means to control the Water direction valve to thereby direct water to the appropriate outlet, and

a water flow control system for regulating the rate of water flow through the water supply line, said water control system including a scale in the discharge conveyor which is depressed by flow of excavated material thereover,

said scale being attached to an air operated actuator which generates an air signal, the intensity of the signal being proportional to the weight of excavated material passing over the scale,

a signal converter and a line connecting the converter to the signal generator,

said converter comprising an air operated positioner having a piston Whose movement is a direct function of the intensity of the air signal, and

a water valve regulator movable with said piston,

said regulator extending into the Water supply valve and being operable, in response to an increase in pressure in the converter, to openthe Water supply valve, and to close it in response to a decrease in pressure in the water converter, whereby th flow of Water for in the supply line may be correlated to the flow of material through the discharge spout.

6. A method of adding water to excavated material passing alternately along a pair of discharge paths from a wheel excavator or the like, said method including the steps of sensing the presence of excavated material at a point along the material flow path upstream from the head ends of a pair of discharge paths,

generating a load signal in response to the presence of excavated material,

the intensity of the load signal being substantially proportional to the quantity of material passing over the sensing point,

directing water against the excavated material as it flows along first one discharge path and then the other, and

regulating the volume flow rate of water in consonance with the intensity of the generated load signal.

7. The method of claim 6 further including the step of delaying direction of Water against the excavated material a length of time sufiicient to enable the excavated material to travel from the sensing point to the water admission point.

8. The method of claim 6 further characterized in that the excavated material is alternately directed along first one discharge path and then the other discharge path in consonance with a direction changing signal, and further including the step of changing the direction of flow of water from one discharge path to the other substantially simultaneously with the change in direction of the flow of excavated material.

9. A method of adding water to agglomerate material at a plurality of selected locations, said method including the steps of sensing the presence of agglomerate material to which water is to be added,

providing a source of Water under pressure,

providing Water flow paths from the source to first and second locations past which said agglomerate material flows, and

directing water from the source against the agglomerate material as it flows first past one location, and then past the other, in coordination with the sensing of the presence of the agglomerate material.

10. The method of claim 9 further characterized in that the presence of agglomerate material is sensed at a point remote from the locations at which Water is added, and further including the step of delaying admission of water to the agglomerate material a length of time approximately suflicient to enable the agglomerate material to flow from the sensing point to the water addition locations.

11. The method of claims 9 further characterized in that the rate of admission of Water is varied in consonance with the amount of agglomerate material passing the sensing point.

12. The method of claim 9 further characterized in that the direction of flow of the Water is changed substantially simultaneously with a change in the direction of flow of the agglomerate material.

References Cited by the Examiner UNITED STATES PATENTS 1,215,559 2/17 Leake. 1,867,817 7/32 Frazee 22257 2,102,584 12/37 Brown 22257 2,510,158 6/50 Van Ackeren 222--57 3,052,050 9/62 Wilms 37-190 3,091,874 6/63 Wuigk 37190 FOREIGN PATENTS 740,716 10/43 Germany.

LOUIS I. DEMBO, Primary Examiner.

BENJAMIN BENDETT, HADD S. LANE, Examiners. 

2. A MOISTURE CONTROL SYSTEM FOR A WHEEL EXCAVATOR OR THE LIKE HAVING AN EXCAVATED MATERIAL FLOW PATH WHICH TERMINATES IN A PLURALTIY OF DISCHARGE AREAS AND MEANS FOR DIVERTING EXCAVATED MATERIAL FROM ONE DISCHARGE AREA TO ANOTHER, SAID SYSTEM INCLUDING, IN COMBINATION, A WATER SUPPLY LINE COMMUNICABLE WITH A SOURCE OF WATER, SAID WATER SUPPLY LINE TERMINATING IN A PLURALITY OF OUTLETS, ONE OUTLET OPENING INTO EACH DISCHARGE AREA, MEANS FOR DIRECTING WATER INTO A MOVING STREAM OF THE EXCAVATED MATERIAL AS IT PASSES THROUGH A DISCHARGE AREA, AND MEANS FOR REGULATING THE QUANTITY OF WATER DIRECTED INTO THE DISCHARGE AREA IN CONSONANCE WITH THE MOVING STREAM OF EXCAVATED MATERIAL PASSING THROUGH THE QUANTITY OF EXCAVATED MATERIAL MOVING ALONG THE FLOW PATH. 